As a result of industrial development, the air, land and water source are excessively polluted. When the waste gas from factories is discharged into air, it will be dispersed and falls down into the land and water source with rain so as to cause more widespread pollution for earth. Moreover, the rain will also wash the dumping of industrial waste into water source area. Although water is adapted to go through the purifying procedures including precipitation, disinfection and exposure after collected, these procedures are still not enough to completely remove all kinds of pollutants. In addition, the chlorine is usually added into tap water during the disinfection process.
Though the permissible mount of chlorine is not harmful to human health, it still makes the tap water smell bad. Furthermore, with the tap water pipes and tanks getting older over time, the tap water can also be contaminated by water equipment. Thus, the tap water for drinking or washing is often passed through a water filter for purification before used, and nowadays reverse osmosis (RO) system is the most popular and common way for water purification, which is adapted to use thin film and reverse osmosis principle to remove ions, molecules and particles from the tap water.
However, the conventional RO system has following disadvantages: (i) the film of conventional RO system is tight, which is adapted to filter out the impurities required for the human body such as minerals, organics, and people may be prone to have osteoporosis and cardiovascular disease when drinking such pure water for a long term; (ii) the filtered water is weakly acidic, which is also not suitable for long-term drinking; and (iii) the use of the conventional RO system is adapted to discharge a large amount of waste water, and the ratio of pure water and waste water even reaches 1:4, which is not environmental friendly. Therefore, there remains a need for a new and improved design for an environmental water system to overcome the problems presented above.